Human endogenous retrovirus-enveloped baculoviral DNA vaccines against MERS-CoV and SARS-CoV2

Abstract

Here we report a recombinant baculoviral vector-based DNA vaccine system against Middle East respiratory syndrome coronavirus (MERS-CoV) and the severe acute respiratory syndrome coronavirus-2 (SARS-CoV2). A non-replicating recombinant baculovirus expressing the human endogenous retrovirus envelope gene (AcHERV) was constructed as a DNA vaccine vector for gene delivery into human cells. For MERS-CoV vaccine construction, DNA encoding MERS-CoV S-full, S1 subunit, or receptor-binding domain (RBD) was inserted into the genome of AcHERV. For COVID19 vaccine construction, DNA encoding SARS-CoV2 S-full or S1 or a MERS-CoV NTD domain-fused SARS-CoV2 RBD was inserted into the genome of AcHERV. AcHERV-DNA vaccines induce high humoral and cell-mediated immunity in animal models. In challenge tests, twice immunized AcHERV-MERS-S1 and AcHERV-COVID19-S showed complete protection against MERS-CoV and SARS-CoV2, respectively. Unlike AcHERV-MERS vaccines, AcHERV-COVID19-S provided the greatest protection against SARS-CoV2 challenge. These results support the feasibility of AcHERV-MERS or AcHERV-COVID19 vaccines in preventing pandemic spreads of viral infections.

The Safe Baculovirus-Based PrM/E DNA Vaccine Protected Fetuses against Zika Virus in A129 Mice

“…Already, we developed a vaccine platform in baculovirus system designed to express a protein that would induce high levels of intracellular delivery in vitro [ 22 ]. Recombinant baculovirus was designed to express eGFP under the control of the CMV promoter, and the HERV envelope gene was inserted downstream of the polyhedrin promoter.…”

“…Another advantage of the AcHERV system is the enhanced cellular uptake of AcHERV due to the presence of HERV envelope proteins on the virus surface. Our AcHERV system efficiently delivers vaccine genes into human cells through type D retrovirus receptor (RDR) binding-dependent endocytosis with multiple boosting [ 22 ].…”

Advances in mRNA and other vaccines against MERS-CoV

“…MERS-CoV DNA vaccines utilize different vectors to encode the full-length MERS-CoV S protein or the S1 subunit. 57,61,65,66 The immunization of NHPs with a synthetic DNA vaccine encoding the full-length MERS-CoV S protein elicited S-specific cellular immune responses and antibodies specific to the full-length S protein, S1 or S2 subunit, and RBD fragment, with lower viral loads and less severity of pathological signs. 57 The vaccine-induced antibody response was able to neutralize MERS-CoV in vitro and protect against MERS-CoV infection in NHPs.…”

Morphological characteristics of X-ray thorax images of COVID-19 patients using the Bradley thresholding segmentation

“…Tiwari and Jain [10] developed an early detection system to differentiate pneumonia from COVID-19 based on the CapsNet network system. Cho et al [11] developed a vaccine system using recombinant baculoviral, DNA-based, to protect the coronavirus syndrome in the Middle East. Leger et al [12] developed a system to determine the severity of COVID-19 based on CT scan images of the lungs.…”